Raiden joins up with private military companies for various jobs including "VIP protection, military training and other duties" as an unspecified country rebuilds from a civil war. "Little does he know that the stage is set for a clash with an enigmatic force of countless cyborgs."
This information comes via the official site, which is also the source for the new screens in our gallery. The site provides a detailed listing of staff for the title, including Platinum's Atsushi Inaba (the guy on stage with Kojima) as producer alongside Konami's Yuji Korekado. It could stand to be more detailed, as there's no game director listed.
Konami still has some revealing to do: the site claims that a video interview titled "The Truth Behind RISING" will explain the genesis of the Platinum/Kojipro collaboration, on December 13.
By the way, the site lists only PS3 and Xbox 360 releases -- no PC.